How do salt flats form in desert basins?

Salt flats, also called playas or salt pans, form in places where water flows into a basin but has no outlet to the sea. In arid climates, that water evaporates quickly, and minerals such as sodium chloride, gypsum, and other salts remain on the surface. After many wet-and-dry cycles, the basin can develop a hard white crust that may crack into polygon shapes. The Bonneville Salt Flats in Utah and the Salar de Uyuni in Bolivia are famous examples. These surfaces can change with rainfall, flooding, and seasonal evaporation.